Ectopic interleukin-5 receptor expression promotes proliferation without development in a multipotent hematopoietic cell line.
The interleukin-5 (IL-5) receptor is a heterodimer that consists of an IL-5 specific alpha subunit and a common ssc chain that is shared with the receptors for granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL-3). In contrast to IL-5, which acts mainly as an eosinophil lineage specific factor in vivo, IL-3 and GM-CSF stimulate the survival, proliferation and development of various hematopoietic cell lineages and also multipotent progenitor cells. IL-5 has little effect on the survival or proliferation of the multipotent stem cell line FDCP-Mix A4 but does promote some eosinophil development. To investigate whether the lineage specificity of IL-5 is due to the restricted expression of the IL-5 receptor alpha subunit we transfected the FDCP-Mix A4 cells with a retroviral vector containing this alpha subunit. The ectopic expression of the IL-5 receptor alpha subunit in the FDCP-Mix cells did not increase the observed eosinophilic development but did stimulate survival and proliferation of the transfected cells when IL-5 was added. IL-5 thus acts like IL-3 in these cells, promoting proliferation and survival. The results suggest that IL-5, whilst having a capacity to promote proliferation, does not influence eosinophilic lineage commitment in these multipotent cells. The results further argue that the observed lineage specificity of IL-5 is probably due to factors in addition to the restricted expression of the IL-5 receptor alpha subunit.
Pierce
A
A
Leukemia Research Fund, Cellular Development Unit, UMIST, Manchester M60 1QD, UK.
Whetton
A D
AD
Owen-Lynch
P J
PJ
Tavernier
J
J
Spooncer
E
E
Dexter
T M
TM
Heyworth
C M
CM
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D015848:Interleukin-5 / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D018123:Receptors, Interleukin / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D053649:Receptors, Interleukin-5; D014162:Transfection
D015848:Interleukin-5; D018123:Receptors, Interleukin; D053649:Receptors, Interleukin-5